1. Field of the Invention
This invention relates to an automobile engine idling stop signal display at an intersection or the like.
More specifically, this invention relates to an automobile engine idling stop signal display apparatus at an intersection or the like to wait for a traffic signal lamp to change.
2. Description of the Related Art
When automobiles wait for a traffic signal to change to red for a predetermined period of time, ordinarily, the drivers wait for the change of the traffic signal while keeping engines in an idling state in most cases. By continuing the engine idling, not only the fuel supplied thereto during the idling time is wastefully consumed but also global warming substances such as carbon dioxide (CO2) and the like and gases such as nitrogen oxide (NOx) and the like which are harmful to human bodies are discharged. To cope with this problem, an xe2x80x9cidling stop campaignxe2x80x9d is being conducted in some districts to promote the idling stop of automobile engines when automobiles are at rest.
Apparatus for controlling the stop of automobile engines have been proposed. The engine stop control apparatus are arranged for temporary stop of the automobile engines when the automobile stops at a red signal or meets a traffic jam. These apparatuses are proposed in the technologies disclosed in, for example, Japanese Unexamined Patent Publication No. 11-62650.
According to the technology disclosed in Japanese Unexamined Patent Publication No. 11-62650, any one of a normal cruising mode or an idling stop/energy saving cruising mode is previously selected by a mode selection switch. In the case that the idling stop/energy saving cruising mode is selected, it is possible to stop an engine at temporary stoppage of an automobile and then to restart the engine, by the ordinary driving operation such as the depression of a brake pedal and the shift operation of a shift lever. By this operation, an idling-stop-controlled automobile can be realized, whereby fuel consumption is saved and atmospheric pollution is prevented in a global scale.
When a driver waits for signal change from red to green or a driver waits for train passing at a lowered gate of a railroad crossing, the driver usually keeps the engine in an idling state without stopping. The reason is to promptly start an automobile just after the red signal is changed to green or gate arm is lifted after train passing. However, gasoline is wastefully consumed by keeping the engine in the idling state during the automobile stoppage.
In addition to the above, the engine discharges global warming substances such as carbon dioxide (CO2) and the like and gases such as nitrogen oxide (NOx) and the like which are harmful to human bodies. Therefore, an xe2x80x9cidling stop campaignxe2x80x9d is being conducted in some districts to promote the idling stop when an automobile is at rest as described above. However, a major reason why the xe2x80x9cidling stop campaignxe2x80x9d does not become widespread resides in the nuisance of stopping an engine.
FIG. 13 shows a discharge characteristic of an amount of nitride oxide (NOx) before and after stopping an engine idling. In the figure, xe2x80x9cixe2x80x9d shows a NOx discharge level in idling state. Numeral t1 denotes a time at which idling is stopped and numeral t2 denotes a time at which an engine is restarted. A slanting-lined region M1 shows an amount of exhaust gas that is reduced by an idling stop. A slanting-lined region M2 shows an excess amount of exhaust gas that is increased by highly concentrated exhaust gas at engine restart, in comparison with the continuous idling.
Thus, no NOx gas is discharged for a period of time t by stopping the idling, and the amount of exhaust gas reaches a peak value that exceeds the level of the idling start by restart of the engine. It is then lowered to the level of the idling state as a time passes. In the case that the region M2 is smaller than the region M1, the idling stop is effective to reduce the exhaust gas. Note that curves showing variations of the exhaust gases, which are similar to that of NOx, are also drawn similarly as to CO2, CO and THC.
However, there are cases in which it is not always preferable to stop idling when an automobile is stopped at a stop signal (red signal) and the like, for example, as shown below.
When an engine is restarted, the amount of fuel required in a cranking process (a process for restarting the engine by rotating a starter motor) is more than the amount of fuel needed in continuous idling. In this case, fuel is much consumed by the idling stop.
When an engine is restarted, harmful exhaust gas are discharged more than that of the exhaust gases discharged in continuous idling. In this case, the harmful exhaust gas is discharged more than that in the idling stop.
A battery load is excessively increased when the headlamps are turned on at night or air conditioning is carried out. In this case, there may be a possibility that the battery goes dead and an engine cannot be restarted.
In the above cases, harmful effects are caused by the stop of idling.
As a reason why xe2x80x9cthe idling stopxe2x80x9d is not widely popularized even though a driver recognizes the effect of it, there is the conventional custom that the driver can not instantaneously recall the idling stop and misses a timing for the action, in addition to the driver""s bothersome feeling of the idling stop action.
Further, still another reason is that the driver may find it unpleasant to have to promptly run an automobile by restarting the engine idling just before signal changes from red to green or just before a crossing gate is lifted.
To solve the above problems, an object of the invention is to provide an idling stop signal display apparatus as an apparatus effective to make an xe2x80x9cidling stopxe2x80x9d campaign become widespread, the apparatus being arranged such that it prompts a driver to stop an engine at a proper timing while a traffic signal device displays a red signal or while the gate arm of a crossing gate is lowered and then notifies the driver of a time at which the engine is to be restarted.
In a particular embodiment of the invention, there is provided an idling stop signal display apparatus connected to traffic relating equipment for prompting a walker or a traveling automobile to stop, comprising display means capable of making a display for prompting an automobile at rest at least to stop an engine and to restart the stopped engine; and control means having a function for determining a time zone during which it is preferable to stop the engine based on the signal input from the traffic relating equipment and causing the display means to make a display for prompting the engine to stop as well as a function for determining a time zone during which it is preferable to restart the stopped engine and causing the display means to make a display for prompting the engine to restart.
The traffic relating equipment may be a traffic signal device installed at an intersection or the like and connected thereto, and the control means divides the time zone during which a red signal is turned on for a predetermined period of time at predetermined intervals in a time series direction based on input red signal display information, and has a function for causing the display means to make a display for prompting the engine to stop in the first divided section of a plurality of divided sections and a function for causing the display means to make a display for prompting the engine to restart in the final section of the plurality of divided sections.
Specifically, in the case that the length of an preceding red signal exceeds a predetermined period of time, the control means may control the display means such that the display means sequentially makes a first display for prompting the engine to stop, a second display for prompting the engine to leave as it is which follows the first display and a third display for prompting to restart the engine, which follows the second display, whereas when the length of the information of the immediately preceding red signal does not exceed the predetermined period of time, the control means may control the display means such that the display means makes only the second display.
Further, the traffic relating equipment may be a crossing gate of a railroad and connected thereto, and the control means may cause the display means to make a display for prompting the engine to stop of the automobile based on a signal input to the apparatus that indicates that a train has approached or a crossing arm has been lowered and to make a display for prompting the engine to restart based on an input signal to the apparatus which indicates that the train has passed.